Dr. Arkenau on the Potential of Immunotherapy in Gastric Cancer

Hendrik-Tobias Arkenau, MD, PhD, medical director, Sarah Cannon Research Institute UK, discusses the potential of immunotherapy in gastric cancer.

Immunotherapy has shown benefit in some patients with gastric cancer, and 2 agents are currently approved in the third-line setting—nivolumab (Opdivo) and pembrolizumab (Keytruda). However, not all patients benefit, so biomarkers such as PD-L1 are used for proper patient selection. Although it has been shown that patients with higher PD-L1 have better outcomes, Arkenau says there are many patients who are PD-L1—negative who derive benefit from immunotherapy.

In gastrointestinal cancer, tumor mutational burden and microsatellite instability (MSI) are often looked to in addition to PD-L1 as predictors of response to immunotherapy. The approval of pembrolizumab in gastric cancer came from a study of patients with MSI-high tumors. Considering studies like these, as well as what has been seen with PD-L1, Arkenau says that the field needs to focus on biosimilar optimization in order to use immunotherapy effectively.